2,2-Dimethyl-1,3-dioxane-4,6-dione → 1-(4-(6,8-Dichloro-2-methyl-1,2,3,4-tetrahydroisoquinolin-4-yl)phenyl)-3-(3-(2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-yl)-3-oxopropyl)urea

Participants

Reaction Conditions

Reaction Steps

Into a 50-mL round-bottom flask purged and maintained with an inert atmosphere of nitrogen, was placed a solution of 3-(3-(4-(6,8-dichloro-2-methyl-1,2,3,4-tetrahydroisoquinolin-4-yl)phenyl)ureido)propanoic acid (200 mg, 0.47 mmol, 1.00 equiv) in dichloromethane (20 mL), N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (136 mg, 0.71 mmol, 1.50 equiv) and 4-dimethylaminopyridine (115 mg, 0.94 mmol, 1.99 equiv). This was followed by the addition of a solution of 2,2-dimethyl-1,3-dioxane-4,6-dione (102 mg, 0.71 mmol, 1.49 equiv) in dichloromethane (2 mL) dropwise with stirring at 0° C. The resulting solution was stirred for 3 h at room temperature. The resulting mixture was washed with KHSO4 (2×10 mL). The mixture was dried over anhydrous sodium sulfate and concentrated under vacuum. This resulted in 240 mg (92%) of 1-(4-(6,8-dichloro-2-methyl-1,2,3,4-tetrahydroisoquinolin-4-yl)phenyl)-3-(3-(2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-yl)-3-oxopropyl)urea as a yellow solid.

Provenance & Evidence